Trench fever is a louse-borne disease caused by
Bartonella quintana and observed originally in military populations during World Wars I and II. Symptoms are an acute, recurring febrile illness, occasionally with a rash. Diagnosis is by blood culture. Treatment is with a macrolide or doxycycline.

Humans are the only reservoir of this
Bartonella infection.
B. quintana is transmitted to humans when feces from infected lice are rubbed into abraded skin or the conjunctiva. Trench fever is endemic in Mexico, Tunisia, Eritrea, Poland, and the former Soviet Union and is reappearing in the homeless population in the US.

Symptoms and Signs

After a 14- to 30-day incubation period, onset of trench fever is sudden, with fever, weakness, dizziness, headache (with pain behind the eyes), conjunctival injection, and severe back and leg (shin) pains.

Fever may reach 40.5° C and persist for 5 to 6 days. In about half the cases, fever recurs 1 to 8 times at 5- to 6-day intervals.

Relapses are common and have occurred up to 10 yr after the initial attack.

Diagnosis

Blood cultures

Serologic tests and PCR

Trench fever should be suspected in people living where louse infestation is heavy. Leptospirosis, typhus, relapsing fever, and malaria must be considered.

The organism is identified by blood culture, although growth may take 1 to 4 wk. The disease is marked by persistent bacteremia during the initial attack, during relapses, throughout the asymptomatic periods between relapses, and in patients with endocarditis.

Serologic testing is available and can provide support for the diagnosis. High titers of IgG antibodies should trigger evaluation for endocarditis. PCR testing of blood or tissue samples can be done.

Treatment

Doxycycline, a macrolide, or ceftriaxone

Although recovery is usually complete in 1 to 2 mo and mortality is negligible, bacteremia may persist for months after clinical recovery, and prolonged (> 1 mo) doxycycline or macrolide treatment may be needed. Patients are given doxycycline 100 mg po bid for 4 to 6 wk plus, if endocarditis is suspected, gentamicin 3 mg/kg/day IV for the initial 2 wk.

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